Making fuel out of thin air

Dresden, Germany (CNN) -- Wouldn't it be great if you could simply grab carbon dioxide from the air and turn it back into fuel?

According to Germany-based renewable energy start-up Sunfire, you can.

"In fact, the idea has been around since at least the 70s," says Christian von Olshausen, the company's Chief Technology Officer. But the process is expensive. "For as long as fossil fuels have been cheap and readily available, there's not been sufficient demand," he adds.

Now -- with the world's finite stock of crude oil on the wane, and amidst pressure to reduce global carbon dioxide (C02) emissions -- the idea of converting those very carbons back into what Olshausen calls "synthetic fuels" is becoming more financially viable.

"The combustion of synthetic fuel does not increase the amount of C02 in the atmosphere," he explains. "This is because the carbon is being continuously recycled."

Synthetic fuel can come in the form of everything from diesel to gasoline to wax. But while the process is simple in theory (see factbox), it is unwieldy in practice -- demanding ultra-high temperatures which gobble up electricity.
"The operation is only practical now that we have relatively cheap sources of renewable electricity to power it," says Olshausen.

Using conventional electricity was never an option, he adds, after all "what's the point of turning carbon into fuel if the electricity you're using to do it burns up more carbon than you started with?"

But this highlights an uncomfortable fact: Sunfire's synthetic fuel contains only 70% of the energy that goes into making it, as heat is lost during the process.
So, why waste hard-won green electricity to produce old-fashioned petrol?

Dr. Jeff Hardy is head of the UK's National Energy Research Network (NERN). He says that, while all efforts should be made to reduce our dependence on liquid fuels, it may not be possible for some industries:

"The thing with fuel is that it offers very high density energy storage ... for areas like long haul aviation, it's hard to see what could replace it."

According to the CIA World Factbook, global oil consumption is currently about 30 billion barrels a year. Hardy points out that, even if we reduce our thirst for fossil fuels to just one or two percent of this figure over the next century, we may still need millions of barrels for things like commercial flight that are unable to use electricity for power.

Could synthetic fuel really plug that gap? At present, Sunfire is moving out of the lab and is talking to car and aircraft-makers in the hope of increasing fuel production to an industrial scale. They are aiming for production to hit one barrel a day within the next few years.

If that doesn't sound like a lot, that's because it's not.

"This is going to be a long process," admits Olshausen. "I'd estimate that it will take between one to two decades before we can replace a single digit percent of current demand (for fuel)."

The problem, he says, is developing materials that can resist extraordinarily high temperatures for long periods of time without degrading.

"But we'll do it," insists Olshausen. "Many innovations in the past century, like the car or the computer, have had to overcome seemingly impossible thermal dynamic obstacles."

Swiss engineer Dominique Kronenberg is certainly hoping that companies like Sunfire will be successful in the long run. He is chief operating officer of Climeworks, a firm that specializes in capturing carbon from the air.

"The question is, what do we do with the carbon once we've got it?" he asks. "At present, the main markets are quite niche -- things like carbonated fizzy drinks, computer cooling systems and industrial greenhouses."

*************

How to create fuel from air
Step one:

Use renewable energy to split water into hydrogen and oxygen with a high-temperature electrolyser

Step two:

Place mixture into a conversion chamber and add carbon dioxide to create "synthesis gas"

It's no surprise then that Kronenberg and his team have been working with Sunfire to flesh out the logistics of a future partnership. The potential market, he says, is a huge and "much more profitable than storing the carbon underground, that's for sure."

No such thing as a good tax - Churchill

To make mistakes is human. To blame someone else for your mistake, is strategic.

SunFire is complicated. It's part of a rather complex cluster of companies around Dr. Bodo Wolf all designed to market his "promising technologies" of biomass gasification or liquification. Wolf himself has been working on such stuff since going independent in 1990, probably after working for some East-German coal mining conglomerate that died with reunification (CV isn't really clear on what he did).

Effectively SunFire is the "replacement" of Choren Industries - not technology-wise, but regarding the primary players. Choren is the current world market leader in biomass gasification technology, but has a little problem - they're going through a controlled insolvency that they've been tumbling towards since Shell withdrew their backing in 2009. €30 million state subsidies going down the drain with them. Choren is also backed by both Daimler and Volkswagen, one of which (probably Daimler) is now backing SunFire.

Effectively Wolf and some other guys from Choren bailed out, shifted some money around and teamed up with a competitor, SunCoal Industries, to create SunFire to market some new technology Wolf pulled out of his backpocket. Von Olshausen, the one that article is all about, is the CEO of SunCoal, and used to be working with Daimler on fuel cell technology.